This guide teaches how to find the proper armhole depth for creating slopers and fitted garments. It covers measuring key points like the shoulder line, chest line, and back shoulder blade to determine the armhole shape and depth, which should be slightly smaller than the final desired fit to allow for adjustments during draping and pattern making.

Steps for Finding Armhole Depth:

1. Locate the bust line, which is typically about 2 inches above the fullest part of the bust on the side seam for a tight fit.
2. Measure the shoulder line by finding the bony protrusion at the top of the shoulder and measuring the width across the front, typically 11-14 cm depending on body size.
3. Mark the shoulder line on the dress form, ensuring it’s parallel to the side seam.
4. Measure the chest line, which is midway between the bust line and neck line, above the fullest part of the bust.
5. Mark the chest line measurement on the dress form, connecting it to the shoulder line markings.
6. For the back armhole, locate the shoulder blade and mark a line about 2 inches above it, connecting it to the chest line marking.
7. Connect the three marked lines (shoulder, chest, and back) to create the initial armhole shape, which should resemble an egg shape with a straighter bottom.
8. This initial armhole shape should be slightly smaller and tighter than the desired final fit, as it will be adjusted and opened up during draping and pattern making.

I always recommend starting with a conservative, slightly tighter armhole measurement, as it’s easier to open it up later than to have to redo everything if it’s too large initially.